Soil meso- and macrofauna in two agricultural systems: factors affecting population dynamics and evaluation of their role in carbon and nitrogen dynamics.
Didden, W.A.M. ; Marinissen, J.C.Y. ; Vreeken-Buijs, M.J. ; Burgers, S.L.G.E. ; Fluiter, R. de; Geurs, M. ; Brussaard, L. - \ 1994
Agriculture, Ecosystems and Environment 51 (1994). - ISSN 0167-8809 - p. 171 - 186.
bedrijfssystemen - organische verbindingen - bodem - bodembiologie - bodemchemie - farming systems - organic compounds - soil - soil biology - soil chemistry
|Aggregate formation by the enchytraeid worm Buchholzia appendiculata and the relationship with organic matter.
Marinissen, J.C.Y. ; Didden, W.A.M. - \ 1994
In: Abstracts 5th Int. Symp. Earthworm ecology. Columbus, Ohio, USA (1994)
|Ecology of terrestrial Enchytraeidae.
Didden, W.A.M. - \ 1993
Pedobiologia 37 (1993). - ISSN 0031-4056 - p. 2 - 29.
|Simulation of nitrogen mineralization in the belowground food webs of two winter wheat fields.
Ruiter, P.C. de; Moore, J.C. ; Zwart, K.B. ; Bouwman, L.A. ; Hassink, J. ; Bloem, J. ; Vos, J.A. de; Marinissen, J.C.Y. ; Didden, W.A.M. ; Lebbink, G. ; Brussaard, L. - \ 1993
Journal of Applied Ecology 30 (1993). - ISSN 0021-8901 - p. 95 - 106.
alternatieve landbouw - hexaploïdie - mineralisatie - modellen - biologische landbouw - onderzoek - triticum aestivum - tarwe - oogsttoename - oogstverliezen - opbrengsten - alternative farming - hexaploidy - mineralization - models - organic farming - research - triticum aestivum - wheat - yield increases - yield losses - yields
|Results of comparative tests of extraction methods for Enchytraeidae.
Graefe, U. ; Didden, W.A.M. - \ 1992
Newsletter on Enchytraeidae 3 (1992). - p. 63 - 78.
A method to construct artificial soil cores from field soil with a reproducible structure.
Didden, W.A.M. ; Marinissen, J.C.Y. ; Kroesbergen, B. - \ 1991
Agriculture, Ecosystems and Environment 34 (1991). - ISSN 0167-8809 - p. 329 - 333.
pedologie - poriënvolume - porositeit - bodembiologie - bodemdichtheid - bodemmicromorfologie - pedology - pore volume - porosity - soil biology - soil density - soil micromorphology
Population ecology and functioning of Enchytraeidae in some arable farming systems
Didden, W. - \ 1991
Agricultural University. Promotor(en): L. Brussaard; L.J. Pons. - S.l. : Didden - 116
Oligochaeta - bodemfauna - veldgewassen - akkerbouw - ecologie - diergedrag - gewoonten - Oligochaeta - soil fauna - field crops - arable farming - ecology - animal behaviour - habits
The population ecology of Enchytraeidae, and their functioning, were studied in some arable farming systems and in laboratory experiments. The systems studied consisted of a 'conventional' (high input of energy and matter) and several 'integrated' (reduced input of energy and matter) systems. Emphasis was given to population dynamics and the role of Enchytraeidae in nutrient cycling and soil structure evolution.
Mean yearly enchytraeid abundance and biomass in the systems studied ranged from 11000 ind/m 2to 43000 ind/m 2, and from 0.08 g C/m 2to 0.42 g C/m 2, respectively. It was calculated that 0.5-3.7% of the yearly organic carbon input was respired by the enchytraeid populations. Yearly nitrogen flux from the populations (through storage in enchytraeid tissue) ranged from 0.19 to 0.60 g/m 2.
There were no significant differences between the systems studied as regards population dynamical and production ecological parameters. However, vertical distribution of enchytraeid populations differed markedly between the conventional field and the integrated fields, probably related with differences in soil tillage and the resulting distribution of organic fertilizer and plant residues. These differences in vertical distribution may have consequences for the risk of nutrients leaching from the systems.
The impact of enchytraeid activity on soil structure evolution was studied in a field experiment with artificial soil cores, in combination with field observations. It was found that enchytraeid activity produced measurable effects on air permeability, pore size distribution, and distribution of aggregate sizes, probably through selective burrowing and transport of organic besides mineral material.
Life-history parameters of Enchytraeus buchholzi, the dominant species at the research site, were determined in a laboratory experiment, and predictions based on the laboratory trials were compared with data on population development under more natural conditions. There were significant discrepancies, indicating an influence of the physiological condition of the experimental animals on the length of the life-cycle in this species.
Involvement of Enchytraeidae (Oligochaeta) in soil structure evolution in agricultural fields.
Didden, W.A.M. - \ 1990
Biology and Fertility of Soils 9 (1990). - ISSN 0178-2762 - p. 152 - 158.
Impacts of earthworms on soil stability.
Brussaard, L. ; Coleman, D.C. ; Crossley Jr., D.A. ; Didden, W.A.M. ; Hendrix, P.F. ; Marinissen, J.C.Y. - \ 1990
In: Proc. 14th Int. Congr. Soil Science (ISSS). - - p. 100 - 105.
aardwormen - bodemstructuur - stabiliteit - bodemtextuur - grondmechanica - deeltjesgrootteverdeling - earthworms - soil structure - stability - soil texture - soil mechanics - particle size distribution
|Reactions of Onychiurus fimatus (Collembola) to loose and compact soil. Methods and first results.
Didden, W.A.M. - \ 1987
Pedobiologia 30 (1987). - ISSN 0031-4056 - p. 93 - 100.